Fluocinolone Acetonide Implant for Uveitis: Dissecting Responder and Non-Responder Outcomes at a Tertiary Center.

Macular edema (ME) remains a primary cause of visual deterioration in uveitis. Visual acuity (VA) can often be maintained using corticosteroid depot systems. This study evaluated the efficacy of a fluocinolone acetonide (FAc) intravitreal implant (ILUVIEN) in treating non-infectious uveitis using real-world data.

Multi-resolution X-ray phase-contrast and dark-field tomography of human cerebellum with near-field speckles.

In this study, we use synchrotron-based multi-modal X-ray tomography to examine human cerebellar tissue in three dimensions at two levels of spatial resolution (2.3 µm and 11.9 µm).

3D X-ray Histology for the Investigation of Temporal Lobe Epilepsy in a Mouse Model.

The most common form of epilepsy among adults is mesial temporal lobe epilepsy (mTLE), with seizures often originating in the hippocampus due to abnormal electrical activity. The gold standard for the histopathological analysis of mTLE is histology, which is a two-dimensional technique. To fill this gap, we propose complementary three-dimensional (3D) X-ray histology.

Retinal blood flow velocities in infants with retinopathy of prematurity after intravitreal administration of bevacizumab.

Background/objectives: Progression of retinopathy of prematurity (ROP) is associated with increased retinal blood flow velocities. We investigated changes of central retinal arterial and venous blood flow after intravitreal administration of bevacizumab.

Subjects/methods: Prospective observational study using serial ultrasound Doppler imaging in preterm infants with bevacizumab-treated ROP.

Apochromatic X-ray focusing.

Achromatic doublets are combinations of two individual lenses designed to focus different wavelengths of light in the same position. Apochromatic optics are improved versions of the achromatic schemes which extend the wavelength range significantly. Both achromatic and apochromatic optics are well-established for visible light.

Zebrafish (Danio rerio) larvae as a predictive model to study gentamicin-induced structural alterations of the kidney.

Nephrotoxicity is an important drug safety aspect to be assessed during drug discovery and development. To study renal toxicity, in vitro cell-based assays are often used. Unfortunately, translating the results of such cell assays to vertebrates including human remains challenging.

Adjuvant therapy for children treated by enucleation at diagnosis of retinoblastoma.

Introduction: Advanced localized retinoblastoma can be cured by enucleation, but extraocular spread of retinoblastoma cells is associated with a high mortality. Risk-stratified adjuvant treatment with chemotherapy and radiotherapy has been shown to reduce the risk for extraocular relapse in children with histopathological risk factors.

Methods: Data of 184 patients with retinoblastoma and primary enucleation were collected in a prospective, multicenter, observational study between 2013 and 2020.

Ruminant inner ear shape records 35 million years of neutral evolution.

Extrinsic and intrinsic factors impact diversity. On deep-time scales, the extrinsic impact of climate and geology are crucial, but poorly understood. Here, we use the inner ear morphology of ruminant artiodactyls to test for a deep-time correlation between a low adaptive anatomical structure and both extrinsic and intrinsic variables.

Three-dimensional analysis of aligner gaps and thickness distributions, using hard x-ray tomography with micrometer resolution.

Purpose: The morphology of a polymer aligner, designed according to an orthodontic treatment plan, determines clinical outcomes. A fundamental element of orthodontic tooth movement with aligner treatment is the fit of the aligner's surface to the individual teeth. Gaps between the aligner and teeth do occur because current aligner fabrication is not capable of completely reproducing the complex anatomy of the individual denture.

Special Section Guest Editorial: Hard X-Ray Tomography with Micrometer Resolution.

JMI guest editors introduce articles collected in the JMI Special Section on Hard X-Ray Tomography with Micrometer Resolution, a snapshot of this important niche area featured by hard x-ray tomography at the micrometer level.

Comparative hard x-ray tomography for virtual histology of zebrafish larva, human tooth cementum, and porcine nerve.

Synchrotron radiation-based tomography yields microanatomical features in human and animal tissues without physical slicing. Recent advances in instrumentation have made laboratory-based phase tomography feasible. We compared the performance of three cutting-edge laboratory systems benchmarked by synchrotron radiation-based tomography for three specimens.

Virtual histology of an entire mouse brain from formalin fixation to paraffin embedding. Part 2: Volumetric strain fields and local contrast changes.

Background: Fixation and embedding of post mortem brain tissue is a pre-requisite for both gold-standard conventional histology and X-ray virtual histology. This process alters the morphology and density of the brain microanatomy.

New Method: To quantify these changes, we employed synchrotron radiation-based hard X-ray tomography with 3 μm voxel length to visualize the same mouse brain after fixation in 4% formalin, immersion in ethanol solutions (50%, 70%, 80%, 90%, and 100%), xylene, and finally after embedding in a paraffin block.

Comparing efficacy and side effects of two systemic chemotherapy regimens for eye-preserving therapy in children with retinoblastoma.

Background: Eye-preserving therapy in retinoblastoma comprises systemic chemotherapy, but studies analyzing the efficacy of different chemotherapy regimens are scarce.

Methods: The efficacy and side effects of two different eye-preserving chemotherapy regimens containing either vincristine, etoposide, and carboplatin (VEC) or cyclophosphamide, vincristine, etoposide, and carboplatin (CyVEC) were compared in a prospective non-interventional observational study including children diagnosed with retinoblastoma between 2013 and 2019 in Germany and Austria. Event-free eye survival (EFES) and overall eye survival (OES) of all 164 eyes treated with both regimens and risk factors were investigated.

Virtual histology of an entire mouse brain from formalin fixation to paraffin embedding. Part 1: Data acquisition, anatomical feature segmentation, tracking global volume and density changes.

Background: Micrometer-resolution neuroimaging with gold-standard conventional histology requires tissue fixation and embedding. The exchange of solvents for the creation of sectionable paraffin blocks modifies tissue density and generates non-uniform brain shrinkage.

New Method: We employed synchrotron radiation-based X-ray microtomography for slicing- and label-free virtual histology of the mouse brain at different stages of the standard preparation protocol from formalin fixation via ascending ethanol solutions and xylene to paraffin embedding.

Mechanistic Illustration: How Newly-Formed Blood Vessels Stopped by the Mineral Blocks of Bone Substitutes Can Be Avoided by Using Innovative Combined Therapeutics.

One major limitation for the vascularization of bone substitutes used for filling is the presence of mineral blocks. The newly-formed blood vessels are stopped or have to circumvent the mineral blocks, resulting in inefficient delivery of oxygen and nutrients to the implant. This leads to necrosis within the implant and to poor engraftment of the bone substitute.

Accuracy of commercial intraoral scanners.

In dental offices, there is a trend replacing conventional silicone impressions and plaster cast models by imaging data of intraoral scanners to map the denture and surrounding tissues. The aim of the study is the analysis of the accuracy of selected commercially available scanners. The accuracy is considered as the main drawback in comparison to the conventional approach.

Behavior of SD-OCT Detectable Hyperreflective Foci in Diabetic Macular Edema Patients after Therapy with Anti-VEGF Agents and Dexamethasone Implants.

Purpose: Diabetic macular edema (DME) is the most common cause of blindness in the working-age population. Spectral-domain optical coherence tomography (SD-OCT) allows detection and monitoring of the edema and a detailed analysis of the retinal structure. Hyperreflective foci (HF) are small, circumscribed lesions on OCT, and their origin is yet to be determined.

Eye Tumors in Childhood as First Sign of Tumor Predisposition Syndromes: Insights from an Observational Study Conducted in Germany and Austria.

Retinoblastoma and other eye tumors in childhood are rare diseases. Many eye tumors are the first signs of a genetic tumor predisposition syndrome and the affected children carry a higher risk of developing other cancers later in life. Clinical and genetic data of all children with eye tumors diagnosed between 2013-2018 in Germany and Austria were collected in a multicenter prospective observational study.

Reentry of endodontic access cavities: composite residue and loss of tooth substance.

The purpose of this study was to investigate the ability of dentists to remove composite fillings from endodontic access cavities using illumination from a conventional light source (CLS) versus the fluorescence-aided identification technique (FIT) in terms of completeness, selectivity and treatment duration. Therefore, two independent operators removed composite resin from six sets of root-filled incisors in a maxillary model under simulated clinical conditions using the CLS or FIT method (twelve teeth per operator and technique). The duration of treatment was recorded and before-after micro-CT scans were superimposed for volumetric assessment of treatment completeness and selectivity.

Vascular findings in primarily affected and fellow eyes of middle-aged patients with Coats' disease using multimodal imaging.

Aims: To investigate the retinal vascular structure and capillary anomalies of affected and fellow eyes of patients with unilateral Coats' disease using multimodal imaging.

Methods: Clinical investigation of both eyes of each patient with diagnosed Coats' disease using ultra-widefield (UWF) fundus imaging, including UWF fluorescein angiography (UWFFA), spectral domain optical coherence tomography (OCT) and optical coherence tomography angiography (OCT-A).

Results: We analysed 38 eyes of 19 patients with unilateral Coats' disease and found that all fellow eyes (19/19; 100%) revealed vascular alterations, detected by UWFFA, predominantly located in the temporal periphery.

Rupture of the Globe: What to Do, What not to Do.

Due to their complexity, globe ruptures are highly compromising traumas for the patient. This is due on the one hand to the eye injury itself with the accompanying loss of vision and on the other hand due to the need for extended treatment with uncertain prognosis and the resulting psychological stress. Globe ruptures are among the prognostically most unfavorable injuries due to the force and peak pressure impacting the eye.

Simultaneous Three-Dimensional Vascular and Tubular Imaging of Whole Mouse Kidneys With X-ray μCT.

Concurrent three-dimensional imaging of the renal vascular and tubular systems on the whole-kidney scale with capillary level resolution is labor-intensive and technically difficult. Approaches based on vascular corrosion casting and X-ray micro computed tomography (μCT), for example, suffer from vascular filling artifacts and necessitate imaging with an additional modality to acquire tubules. In this work, we report on a new sample preparation, image acquisition, and quantification protocol for simultaneous vascular and tubular μCT imaging of whole, uncorroded mouse kidneys.

Shedding Light on Metal-Based Nanoparticles in Zebrafish by Computed Tomography with Micrometer Resolution.

Metal-based nanoparticles are clinically used for diagnostic and therapeutic applications. After parenteral administration, they will distribute throughout different organs. Quantification of their distribution within tissues in the 3D space, however, remains a challenge owing to the small particle diameter.

Crosslinkable polymeric contrast agent for high-resolution X-ray imaging of the vascular system.

A contrast agent for X-ray micro computed tomography (μCT), called XlinCA, that combines reliable perfusion and permanent retention and contrast properties, was developed for ex vivo imaging. The new imaging agent XlinCA features high molecular weight, low viscosity and a high iodine content.